#include<iostream.h>
int factorial(int);
void main()
{
	int num=1;
	for(int i=-1; i<num; i++)
	{
		cout<<"Enter a number?:";
		cin>>num;
		cout<<factorial(num);
		cout<<endl;
	}
}
int factorial(int num)
{
	if (num<0) return 0;
	int f=1;
	while(num>1)
		f*=num--;
	cout<<"The factorial is "<<endl;
	return f;
}